for the NAC. 'The problem with tracking down the cause of asthma is that

what may be a trigger for the condition in one person will not be the same

trigger for another sufferer.'

The NAC says a trigger is 'anything that irritates the airways and causes

the symptoms of asthma to appear'. Common triggers include colds or flu,

cigarette smoke and an allergy to things like pollen from flowers,

house-dust mites or pets with fur or feathers. House-dust mites live in

soft furnishings, duvets, carpets and curtains in every home in Britain.

Experts believe adult asthma may also be caused by a combination of other factors, including

genetics, lifestyle and environment. If you are the older child, for example,

it's thought you may be more susceptible to asthma as your immune system will

not have had the same chance to develop as your younger siblings. This is because you will not have had brothers or sisters to interact with as a child and so will have been exposed to fewer bugs, which usually help to strengthen your immune system.

If you work in a particularly smoky atmosphere or are a smoker yourself, you might

be more at risk of developing adult asthma.

So how can you tell if you have adult asthma rather than just the

left-overs from a cold or flu? 'If you are coughing a lot, especially at

night, if you are wheezing and your chest feels tight, then it is worth

getting it checked out by your doctor,' advises Kirsty. Even if you only

have one of the symptoms, it is still worth going to see the doctor if you

are concerned.

If you are diagnosed with asthma, there is no need to panic. Your condition

can be managed safely and effectively - just ask Paula Radcliffe, the

100,000 metre world champion and an asthmatic.

For more information,

contact the National Asthma Campaign Helpline on 08457 01 02 03 or visit